The electrical turn signals commonly found on automotive vehicles are designed to be manually operated and to automatically disengage after the steering wheel is straightened out after completing a turn. However, the turn signal too frequently does not automatically disengage after it has been manually engaged. Sometimes the turn signal mechanism becomes faulty and it will manually engage but will not automatically disengage. Most often, however, a turn is too slight to activate the disengagement mechanism to turn off the turn signal. This occurs all the time when using turn signals and changing lanes. The lane change is completed but the turn signals stay on giving a false indication of the drivers intent to turn or to change lanes. Normally, at lower driving speeds a driver would detect that a turn signal remains engaged after a lane change by hearing the clicking of the blinker mechanism, but at highway driving speeds the engine noise and wind noise level inside a car is high enough that the clicking sound cannot be heard.
It is therefore desirable to provide a warning signal that indicates turn signals remain active for more than a predetermined amount of time after they have been engaged.
Prior art turn signal warning devices have problems. Some warning devices can only work in vehicles in which brake lights and turn signal lights are separate. With these devices a driver will often be in a turn lane with their turn signal on and the audible warning signal will engage. This happens because they are in the turn lane more than the timeout period of the warning device. Another problem with these warning devices is that they trigger when emergency flashers are utilized.
Other turn signal warning devices can only work in vehicles in which the same light bulbs are used as brake lights and turn signal lights. A problem with these warning devices is that they also trigger when emergency flashers are utilized.
Thus, there is a need in the art for a single turn signal warning device that can work both in vehicles in which turn signal lights are separate from brake lights, and in vehicles in which the same light bulbs are used for both turn signals and brake signals.
In addition, there is a need in the art for a turn signal warning device that will not be engaged when emergency blinkers are utilized, or when a brake pedal is depressed for a period of time, or when a turn signal is deliberately engaged for a longer than normal period of time because the vehicle is in a turn lane waiting to turn.